1. Field of the Invention
The present invention relates to a method for manufacturing a linkage terminal mounted in a housing of a joint connector.
2. Description of the Related Art
As a connector using a linkage connector, there has been known a connector assembly disclosed in Japanese Patent Publication (JP-A) No. 8-64314. As illustrated in FIG. 1, after lead frames 2, 3 each including a plurality of contacts 1 are stacked and welded continuously, an insulation block 4 is fixed to the lead frames which have been welded, and strip-shaped carriers of the lead frames 2, 3 are removed. As shown in FIG. 2, each contact 1 of the connector having such a structure is inserted in a contact accommodation space formed in another insulation housing block 5.
In the above conventional connector, however, as the lead frames 2, 3 are continuously welded, there is a drawback that a welding time is extended and productivity is limited by the welding time.
Also, the insulation housing blocks 4, 5 have structures different from each other so that insulation housing blocks of kinds of the number corresponding to the number of layers must be prepared in a multi-layer structure of the insulation housing blocks 5.
Also, since the lead frames 2, 3 must be cut in their stacked state, there is a drawback that it is difficult to cut the lead frames 2, 3
In this manner, in the conventional connector, as much manufacturing time is taken, it is difficult to reduce manufacturing cost. Also, as the contacts 1 are bent after the lead frames 2, 3 have been stacked double, there is a drawback that, when the carrier portions of the lead frames 2, 3 are welded, stress is liable to be applied on the welded portions, which may be peeled off by the stress.
Therefore, an object of the present invention is to provide a linkage terminal of a joint connector which can be manufactured with a high manufacturing efficiency and where secure electrical connection can be made.
In order to achieve the above object, a manufacturing method of a linkage terminal mounted in a housing of a joint connector according to the present invention comprises a first step and a second step. In the first step, a first terminal element and a second terminal element are shifted in their longitudinal directions relative to each other and stacked one on the other. Each of the terminal elements has a strip-shaped carrier and terminals formed integrally with the carrier. The terminals are arranged along the longitudinal direction of the carrier at equal intervals and extend from the carrier generally perpendicularly to the carrier. In the second step, the carriers of the first and second terminal elements are mutually welded along their longitudinal direction.
According to the above method, carriers of first and second terminal elements are mutually welded so that distances or intervals between terminals can be made small. As a result, a housing of a joint connector in which a linkage terminal is mounted can also be made compact.
In the second step, the carriers may be welded intermittently along their longitudinal directions.
According to the above method, as carriers are welded intermittently, a time required for welding is shortened, which results in reduction in manufacturing cost.
In the first step, the first terminal element and the second terminal element are stacked in a state where they are shifted relative to each other by half of a pitch between terminals in longitudinal directions of the carriers.
According to the above method, first and second terminal elements are shifted by half of a pitch, so that terminals can be disposed at equal small pitches between adjacent terminals.
In the second step, portions of the carriers from which the terminals extend may be welded.
According to the above method, as only portions of carriers corresponding to terminals have been welded, portions of the carriers to be cut are not welded and they can easily cut off. Thereby, a productivity can be improved.
The method further comprises a step for cutting the carriers along directions perpendicular to their longitudinal directions according to the number of terminal accommodation portions of the housing of the joint connector after the carriers may be welded.
According to the above method, as the carriers are cut corresponding to the number of terminal accommodation portions of a housing where a linkage terminal is accommodated, the linkage terminal can be provided with a configuration where it can immediately used in a joint connector.
The method further comprises a step for bending boundary portions between the carriers and the terminals such that the terminals are arranged with the same height after the carriers may be welded.
According to the method, as height positions of terminals can be adjusted by a bending machine, a linkage terminal with an excellent assembling easiness to a housing of a joint connector can be provided.
In the bending step, the boundary portions are bent by a bending machine.
According to the above method, as height positions of terminals can be adjusted by a bending machine, a linkage terminal with an excellent assembling easiness to a housing of a joint connector can be provided.